[XPERIA X10 Android Development] Nikhil_007:
Nand: Implement raw read/write and biterr

I was wondering as to y READ isnt working on MTD mode, I got answer from one of goroh's post going back few pages, its basically a problem with ECC Calculation.

I dig a bit deep and found few usefull links and also a patch for bypassing ECC. can u pl try as im in office right now and cant connect my X10 and have disbled USB port. also limited access to resources. I ill try looking in more once i get some time.

New commands nand read.raw and write.raw read/write

main and oob area.

Implement previously stubbed nand biterr command.

Document the above and also the previously undocumented

read.oob and write.oob.

---

common/cmd_nand.c | 115 +++++++++++++++++++++++++++++++++++++++++++++++++++-

1 files changed, 112 insertions(+), 3 deletions(-)

diff --git a/common/cmd_nand.c b/common/cmd_nand.c

index 158a55f..a488038 100644

--- a/common/cmd_nand.c

+++ b/common/cmd_nand.c

@@ -90,6 +90,95 @@ static int nand_dump(nand_info_t *nand, ulong off, int

only_oob)

return 0;

}

+#define NAND_RW_RAW_READ 0

+#define NAND_RW_RAW_WRITE 1

+

+static int nand_rdwr_raw(int rdwr, nand_info_t *nand, ulong off, u_char *buf,

+ size_t size)

+{

+ struct mtd_oob_ops ops = {

+ .len = nand->writesize,

+ .ooblen = nand->oobsize,

+ .mode = MTD_OOB_RAW,

+ };

+ int i;

+ int nrblocks = size / nand->writesize;

+ loff_t addr = (loff_t)(off & ~(nand->writesize - 1));

+

+ while (nrblocks--) {

+ ops.datbuf = buf;

+ /*

+ * for read oobbuf must be set, but oob data

+ * will be appended to ops.datbuf

+ * for write oobbuf is actually used

+ */

+ ops.oobbuf = buf + nand->writesize;

+ if (rdwr == NAND_RW_RAW_READ)

+ i = nand->read_oob(nand, addr, &ops);

+ else

+ i = nand->write_oob(nand, addr, &ops);

+ if (i < 0) {

+ printf("Error (%d) %s page %08lx\n", i,

+ rdwr == NAND_RW_RAW_READ ?

+ "reading" : "writing",

+ (unsigned long)addr);

+ return 1;

+ }

+

+ addr += nand->writesize;

+ buf += (nand->writesize + nand->oobsize);

+ }

+ return 0;

+}

+

+static int nand_read_raw(nand_info_t *nand, ulong off, u_char *buf,

+ size_t size)

+{

+ return nand_rdwr_raw(NAND_RW_RAW_READ, nand, off, buf, size);

+}

+

+static int nand_write_raw(nand_info_t *nand, ulong off, u_char *buf,

+ size_t size)

+{

+ return nand_rdwr_raw(NAND_RW_RAW_WRITE, nand, off, buf, size);

+}

+

+static int nand_biterr(nand_info_t *nand, ulong off, int bit)

+{

+ int ret = 0;

+ u_char *buf;

+ ulong blockoff = off & ~(nand->erasesize - 1);

+ int byteoff = off & (nand->erasesize - 1);

+ nand_erase_options_t opts = {

+ .offset = blockoff,

+ .length = nand->erasesize,

+ };

+

+ buf = malloc(nand->erasesize +

+ nand->oobsize * (nand->erasesize / nand->writesize));

+ if (!buf) {

+ puts("No memory for page buffer\n");

+ return 1;

+ }

+ nand_read_raw(nand, blockoff, buf, nand->erasesize);

+

+ ret = nand_erase_opts(nand, &opts);

+ if (ret) {

+ puts("Failed to erase block at %x\n");

+ return ret;

+ }

+

+ printf("toggling bit %x in byte %x in block %x %02x ->",

+ bit, byteoff, blockoff, buf[byteoff]);

+

+ buf[byteoff] ^= (1 << bit);

+

+ printf("%02x\n", buf[byteoff]);

+

+ nand_write_raw(nand, blockoff, buf, nand->erasesize);

+ free(buf);

+ return 0;

+}

/* ------------------------------------------------------------------------- */

static inline int str2long(char *p, ulong *num)

@@ -401,6 +490,13 @@ int do_nand(cmd_tbl_t * cmdtp, int flag, int argc, char

*argv[])

ret = nand->read_oob(nand, off, &ops);

else

ret = nand->write_oob(nand, off, &ops);

+ } else if (!strcmp(s, ".raw")) {

+ if (read)

+ ret = nand_read_raw(nand, off,

+ (u_char *)addr, size);

+ else

+ ret = nand_write_raw(nand, off,

+ (u_char *)addr, size);

} else {

printf("Unknown nand command suffix '%s'.\n", s);

return 1;

@@ -437,9 +533,19 @@ int do_nand(cmd_tbl_t * cmdtp, int flag, int argc, char

*argv[])

}

return ret;

}

-

if (strcmp(cmd, "biterr") == 0) {

- /* todo */

+ off = (ulong)simple_strtoul(argv[2], NULL, 16);

+ i = (int)simple_strtoul(argv[3], NULL, 16);

+

+ int ret = nand_biterr(nand, off, i);

+ if (ret == 0) {

+ printf("byte offset 0x%08lx toggled bit %d\n",

+ (ulong) off, i);

+ return 0;

+ } else {

+ printf("byte offset 0x%08lx could not toggle bit %d\n",

+ (ulong) addr, i);

+ }

return 1;

}

@@ -494,13 +600,16 @@ U_BOOT_CMD(nand, CONFIG_SYS_MAXARGS, 1, do_nand,

"nand write - addr off|partition size\n"

" read/write 'size' bytes starting at offset 'off'\n"

" to/from memory address 'addr', skipping bad blocks.\n"

+ " .oob - reads/writes oob only.\n"

+ " .raw - reads/writes both main and oob with no error\n"

+ " detection or correction\n"

"nand erase [clean] [off size] - erase 'size' bytes from\n"

" offset 'off' (entire device if not specified)\n"

"nand bad - show bad blocks\n"

"nand dump[.oob] off - dump page\n"

"nand scrub - really clean NAND erasing bad blocks (UNSAFE)\n"

"nand markbad off [...] - mark bad block(s) at offset (UNSAFE)\n"

- "nand biterr off - make a bit error at offset (UNSAFE)"

+ "nand biterr off bitno - toggle bit bitno in byte off (UNSAFE)\n"

#ifdef CONFIG_CMD_NAND_LOCK_UNLOCK

"\n"

"nand lock [tight] [status]\n"

Also ther are few usefull links which shld work or atleast b usefull...

http://140.211.166.79/mailarchive/git-commits-head/2010/5/21/37439

http://lists.denx.de/pipermail/u-boot/2009-November/063930.html ( i think tis is intresting)

http://lists.denx.de/pipermail/u-boot/2009-November/063930.html

EDIT: Did u tried this?

* Read raw data from the device without ECC */

extern int nand_read_raw (struct mtd_info *mtd, uint8_t *buf, loff_t from, size_t len, size_t ooblen);